In 2007, the scientific and medical ground shifted at the Conference on Retroviruses and Opportunistic Infections when word emerged of the first patient whose HIV had apparently disappeared after two bone marrow transplants. At the time known only as “The Berlin patient,” Timothy Ray Brown had undergone the transplant procedures for leukemia (not HIV) only after chemotherapy had failed; his marrow donor possessed a genetic mutation, CCR5-delta 32, which in essence “locks” the HIV virus out of immune cells. (The mutation, which to date has been found only in European populations and particularly among Swedes, confers immunity to HIV if two copies of the mutation are present.)
Mr. Brown’s case was particularly dire. He was gravely ill before his transplants and experienced significant complications after the surgery, including an induced coma. He nearly died at one point during his long, complicated recovery. And so, while his status as the first known patient to clear the HIV virus from his body and survive 12 years (and counting), physicians and researchers have been pursuing marrow transplantation and HIV research in the hopes that such treatment would not entail such potentially serious complications.
In March 2019, the case of a second patient, “The London Patient,” was presented at the same conference, and this time, while the patient chooses to remain anonymous, the results are extremely encouraging—without the use of harsh, destructive immunosuppressive drugs that made Brown’s treatment so taxing. Like Brown, the London Patient underwent a marrow transplant for cancer, and like Brown, the second patient’s transplanted immune cells with the CCR5 mutation, which are resistant to HIV, have apparently replaced his own. After one year after stopping anti-retroviral drugs, the London patient remains virus-free.
And the news gets better still. Just a few days after news of The London Patient broke, a third case made headlines: while the Dusseldorf Patient is still quite early in remission at just three months off antiretrovirals, three patients experiencing what knowledgeable experts are cautiously calling a “cure” is a gamechanger. And it provides a clear pathway for further development.
Bone marrow transplants will not, experts rush to clarify, be a widespread remedy for AIDS. They are incredibly taxing, risky, complex, and carry a significant risk of rejection. In addition, there is an exceedingly small pool of available donors with the CCR5 mutation.
But taken together, these three cases offer breathtaking vistas of a new horizon in AIDS and HIV research—one that may finally point in the direction of a true cure, not just prevention and treatment.